Combined protractor



(No Model.)

J. DUCKWORTH & E. SMITH. GOMBINBD PROTRAGTUR, SQUARE, AND BEVBL. No. 282,966. 'nted Aug. 14, 1883.

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WITNESWSES NIO , UNITED STATES* PATENT OFFICE'.-

.IAMES nUoKwoETH AND ELI SMITH, or SPRINGFIELD, MASSACHUSETTS.

COMBINED 'PROTRACTO'R,`SQUARE,` AND Bravi-:iml

SPECIFICATION forming part of Letters Patent. No. 282,966, dated August 1.4, 1883.

i A Application filed June 22, 1883. (No model.)

To fr# w/tam, it may concern.-

Beit known that we, J AMES DUoKwoETH and ELI SMITH, citizens of the United States, residing at Springfield, in the county of Hampden and State of Massachusetts, have invented new and useful Improvements in Combined Protractor, Square, and Bevel, of which the ,following is a specification. y

This invention relates to an improved tool consisting of a protractor, square, and `bevel combined in one instrument, provision being also made in the same `tool to embody therein a level, the object being to embrace in an ordifrs nary bevel all of the above-mentioned devices, combining therewith improved mechanism for locking the blade at fright angles to the stock and for setting an angle-stop therefor for indicating any desired angle of incline of the blade and for locking the latter in any position.

In the drawings formingpart of this specification, Figure 1 is a side elevation, and Fig. 2 is a longitudinal Section, of atool constructed according' to our invention. Figs. 8, 4t, 5, 6 and 7 are detail views.

In the drawings, a a are the two parts of the stock of the tool which inclose the slotted blade c between them in the usual manner, the Screw e passing through the ends of the stock parts and the slot in the blade, serving as a point upon` which the blade swings to different. angles.

The blade cis provided with a groove,

` fw, near one'edge `and parallel therewith.

The side a ofthe stock has on its interior a boss, `7, to which is secured, as shown, a bladeholder, h, having` on its free end two teeth, 6 6, and on its face, 'near the latter, abladestop,

`5. The blade-holder is capable of having a vibratory movement given toits free end by means operative from the outside ofthe stock,

and the means herein shown consist of atongue, b2, one end of which lies between an inclined surface, c2, on the stock and the adjoining side of saidholder. The opposite end of thetongue b2 is bent and made to project through a slot in the stock, and has attached thereto a roughened plate, b. Sliding plate b toward the blade c drives the end of tongue b2 bein a right-angle position, as in Fig. l, causing I said teeth to enter the groove fw in the blade and hold the latter in that position. By drawing tongue b2 back the holder springs away from the blade, leaving it free to be`turned to other positions. A screw, passing through the part a against, the side of holder 71, may be used for forcing the latter against the blade; but it would be inconveniently in the way.

Holder h has an anglestop for blade c, thereupon indicated by 5. Said angle-stop is so located that it will stop the blade at an angle of forty-iive degrees to the Stock, when, after swinging the blade slightly to carry groove` w out of line with the teeth 6, the holder h is, as above described, made to spring against the blade and move stop 5 forward, so that the an indicator-line, S. An angle-indicator, w,

provided withgraduation-lines 3 on its pe-` riphery, anda bar, a?, across one side, is fitted into said socket in the part a, ofthe stock, its bar nglitting into the slot in blade c, and screw e passing through it and indirectly through the blade-slot. Vhen the indicator n. and the blade c are properly hung to oscillate in the end ofthe stock, the lines 3 on the periphery of said indicator are visible through the opening o at the end ofthe stock, and, by turning the blade to bring one of lines 3 (either side ofthe centerone) on a line with line 8 on the stock, the blade is brought to a certain angle ofinoline, which angle' or angles may be marked by figures stamped at' said lines,`so' that the operator can at once turn the blade to any desired angle of' incline, the degree of which is indicated by the gures to accompany the said lines 3 on the indicator a.

The part a of the stock is provided with a pointed screw-rod, d, working in a tapped bar, y y, and provided witha thu1nb-piece for turning it, as shown. The rounded end ofthe tween the holder hand the incline c2, making p, the end ofthe holder on which are teeth 6` 5o spring toward blade 0, and when the latter is stock part a/ is provided with a lever and washer-socket, in the center of which rises the stud c2. Into the bottom of said socket is Ioo 'Ihe above-mentioned screw-rod d, lever m,

and washer o, constitute the devices by which the blade c is clamped in the stock and rigidly secured in any position to which it'may be turned, as aforesaid, and said devices operate as follows: When the screw-rod d is turned to draw its point away from under arm mi'on lever m, the latter and washer o drop away from the side of blade c, leaving it free to swing; but screwing rod (l forward` and forcing its point under arm m2 causes lever m to be moved toward said blade, and its highest central position t0 be forced against washer 0,- pushing the latter against blade c, and clamping the latter tightly between the endsv of the stock.

The construction of the lever m,with the arm m2 thereon, gives increased `power without iny creasing the general diameter of the lever, and making it highest in the center causes it to so bear against washer o, letting the latter rock thereon, as to permit the washer to come, to a perfectly ilat bearing against the side of blade c, and make such a frictional bearing thereagainst as to firmly hold the blade.

In setting blade c to form a square, as in Fig. l, the blade is turned nearly to that position. Plate b is pushed ktoward the blade, making the teeth 6 on the holder h engage in groove w and swing the blade to a correct position. Screw d is then forced under lever m, thus firmly securing the blade in position. To free the blade, retire screw d from lever m and slide back plate, b.

'I0` provide a practicable level in connection with this tool, a suitable bubble-glass pocket is formed in one edge of the part c of the stock, in which is located a bubble-glass, D, of crdinary construction. (Shown in dotted lines in Fig. 3.) Y Vhat we claim as our invention is- 1. The combination, with they stock and blade of a bevel, of the circular angle-indicatore, having a bar, a2, thereon to interlock with said blade, and having graduation-lines across its periphery arranged to be brought into coincidence' with an Yindicator-line on the stock, substantially as set forth.

2. In combination, with the stock of a bevel, a blade having the usual slot therein, and provided with a groove near to and parallel with its edge, a vibratory blade-holder attached to said stock, and having teeth thereon to engage in said groove, and means, substantially as described, for operating said holder to e11- gage it with. and disengage it from said blade, substantially as set forth.

3. In combination with the stock and blade of a bevel, the vibratory blade-holder h, having the stop-pin 5 thereon, the plate Z1, and tongue b2, substantially as set forth.

, 4. The combination,with the blade and stock of a bevel, of the pointed screw-rod d, the cir-v cular lever m, having arm m2 thereon, and-of greater thickness at its center than at its border, and the washer o, interposed between lever m and the blade o, substantially as set forth.

1 3. In combinationwith the stock of a bevel and with the bladethereof, having a groove therein parallel with and near to one edge, the vibratory blade-holder la., having the stop-pin 5 and the teeth G thereon, and the tongue b2 operative from outside the stock, substantially as set forth. v

` JAMES DUCKXVORTH.

ELI SMITH.

IVitnesses:

H. A. CHAPIN, J. D. GARFIELD. 

